Analysis of ride comfort of high-speed train based on a train-seat-human model in the vertical direction

Abstract

A rigid-flexible coupled train-seat-human model was developed for studying ride comfort of rail vehicles. The weighted acceleration r.m.s. value at the seat pan was used for assessing ride comfort. The contribution of different modes of the carbody to ride comfort was defined from the perspective of power spectral density. The role of first bending mode was more important than other bending modes when bogie and seat positions are far from the nodes of first bending mode. Under this situation, the bogie spacing filter effect of first bending mode can be adopted to predict peaks and troughs of the equivalent acceleration on the floor or human-seat interface varying with speed or first bending frequency. The incorporation of human-seat system was necessary in order to accurately evaluate ride comfort. The ride comfort exhibited a global trend of improvement with increased bending rigidity or reduced speed. Increasing the damping ratio of bending modes improved ride comfort effectively. Increasing stiffness or decreasing damping of human-seat vertical contact on the seat pan worsened ride comfort. Equivalent accelerations at symmetrical seat positions showed analogous tendency as the speed. Ride comfort was worst at two ends whatever the speed was, followed by carbody centre at high speed.